Have you ever had trouble sleeping in a new place?

    Lots of people do. And now researchers from Brown University in Rhode Island think they know why. They found that one-half of the brain "remains more awake" than the other half when people are trying to sleep in a new place.

The sleep findings were reported in Current Biology by Brown University. In their report, the researchers said many people report they have a harder time sleeping the first night at a hotel or other places outside their home. They call it "first-night influence". "In Japan they say, 'If you change your bed, you can't sleep,'" said Yuka Sasaki, one of the report's writers. "You don't sleep very well in a new place. We all know about it."

    The researchers measured brain waves (测量脑波) for 35 volunteers over two nights in a laboratory. The two nights were a week apart (间隔). They found during the first night the left half of the brain was more active than the right half. This was during the first deep-sleep period, the researchers said.

    Sasaki said a lot of questions remain.

    Researchers did not keep measuring brain waves all night long. So, they don't know if the left half keeps "watch" all night, or whether it "works in shifts (轮换) with the right half later in the night". They also do not know why the brain activity, at least during the first period of deep sleep, is always on the left half.

    For some, this research may be calming. It is good to know that our brain is "looking out for us" in a new place. But it may not help with sleep. That brain activity, at least according to this new research, makes it harder to get the sleep people need to wake up well rested in the morning.

    Most teens need more than 9 hours of sleep each night. But about 1 in 4 teens has trouble in sleeping. Lack of sleep can affect everything from our feelings to how well we focus on tasks like studying. It can also influence sports performance, increase our chances of getting sick, and may lead to weight gain in some people.

    How can we get the sleep we need? Here are some ideas:

    Be active during the day. Get at least 60 minutes of exercise a day. Physical activity can decrease stress and help people feel more relaxed. Just don't work too close to bedtime because exercise can wake you up before it slows you down.

    Say goodnight to electronics. Experts suggest using the bedroom for sleep only. At least shut everything down an hour or more before lights out.

    Keep a sleep routine. Going to bed at the same time every night helps the body expect sleep. Creating a bedtime routine can improve this relaxation effect. Reading, listening to music, spending time with a pet, writing a diary or doing anything else can relax you.

    Expect a good night's sleep. Instead of worrying that you won't sleep, remind yourself that you can. Say "Tonight, I will sleep well." several times during the day. It can also help to practise breathing exercises or gentle exercises before bed.

    Everyone has a sleepless night once in a while. But if you regularly have trouble in sleeping and you think it's affecting your mood or performance, talk to your doctor.

Do you know many students aren't healthy?

Now many students know sports are good for their health. {#blank#}1{#/blank#} Some of them only watch them on TV. What's more(而且), many of them only like watching TV and playing computer games. They often say, "{#blank#}2{#/blank#} Play basketball? Oh, it sounds difficult. "

{#blank#}3{#/blank#} They don't have carrots for lunch and they don't have tomatoes for dinner. But vegetables and fruit are healthy food. {#blank#}4{#/blank#} But they like junk food (垃圾食品). {#blank#}5{#/blank#}

If (如果) you would like to be healthy, eat vegetables and play sports every day.